class Student(object):
    def __init__(self,name,age):
        self._name = name
        self._age = age

    def set_name(self,name):
        self._name = name

    def get_name(self):
        return self._name

    def print_age(self):
        print('%s: %s' % (self._name, self._age))

    def get_age(self):
        if self._age<18:
            return '青少年'
        elif self._age==18:
            return '刚好成年'
        else:
            return '要承担法律责任了'


stu = Student('张三',18)
print(stu.get_name())
stu.print_age()
print(stu.get_age())